Children should be given only water or milk and should not expect sweet drinks all the time, according to senior government advisers. They point out that fruit juices are helping fuel sharp rises in obesity rates, type 2 diabetes and heart disease

The Government body responsible for tackling obesity is likely to recommend a levy of up to 20 per cent – raising the price of a 40p can of Coke to 48p and a 2.5litre carton of fruit juice from £2.50 to £3.

The Government is expected to reject this advice and last week the Health Secretary insisted there were no plans for a sugar tax.

Jeremy Hunt said the food industry was successfully lowering sugar levels in products voluntarily under the Government’s responsibility deal with firms.

But experts have criticised the scheme, saying it is not doing enough to combat rising obesity rates.

Nearly a quarter of adults are considered obese – a proportion that is expected to rise to a half by 2050.

Also tomorrow, the Government’s scientific advisory committee on nutrition will publish guidelines on sugar limits.

Current recommendations state it should be no more than 12 and 13 teaspoons of sugar a day although the experts may conclude we should aim for much less.

Only last week the Government announced that school milk would be provided for all pupils in the hope of slashing consumption of fizzy drinks and fruit juice. It will be free for the under-fives but older pupils will be charged.